During the construction of houses and commercial buildings, the basic building framework first is "roughed-in". This includes, in most cases, the erection of the wall structures in the form of wood or metal studs attached to floor plates and top plates to form the exterior and interior walls. After this stage of construction has been completed, electrical outlet boxes and junction boxes are attached to the studs; and the electrical wiring for the building is put in place either through conduit or in the form of insulated plastic sheathed wiring. All of this is done prior to the enclosure of the wall studs by the interior wall surfaces.
In the rough construction phases, the location of electrical boxes for outlets, wall switches and some junction boxes must be determined vertically from the floor. The boxes also must be mounted to extend outwardly from the front surface of the studs (such as two-by-four wood studs) a predetermined amount established by the thickness of the finished wall materials which are to be placed over the studs after the electrical boxes are attached and the necessary wiring has been completed.
To accomplish this, two measurements must be made each time an electrical outlet box is to be attached to a vertical stud. First, the vertical distance from the floor must be determined (and this distance is different for wall outlet boxes and switch outlet boxes). Then the amount by which the box is to extend beyond the front surface of the stud also must be established. Once these measurements have been made, the outlet box is nailed in place.
Typically, the studs to which outlet boxes and switch boxes are to be attached first are marked. The electrician then either independently measures the vertical height for locating the various boxes or utilizes a precut measuring stick on which the different box heights for the building under construction are marked. A mark is placed on the stud parallel with either the top or the bottom of the outlet box. After the measurements have been effected, the box is nailed in place. While this technique usually provides a relatively accurate vertical location of the outlet box on the stud, the amount that the box extends beyond the edge of the stud usually is not separately measured, but is approximated by the electrician when the box is nailed in place. Consequently, in some situations the box is recessed too far and in others, it extends beyond the finished wall of the completed construction.
It is readily apparent from a consideration of the foregoing that the measurement and placement of electric boxes for attachment to the wall studs, in the manner described, is a relatively time consuming, multiple step process. This process also inherently is subject to inaccuracies or improperly mounted boxes.
In the past, a variety of different devices have been devised for assisting in the mounting of electrical boxes on studs of a building under construction. Some such mounting devices have a flange or projection on them for inherently providing the proper amount of projection of the box past the stud, so that it is flush with the finished wall in the final construction. These devices, however, do not provide any assistance in proper vertical location along the length of the stud. In addition, the positioning device remains permanently in place and forms an integral part of the mounting of the box itself. Consequently, electrical boxes which incorporate these locating aids necessarily are more expensive than the basic hollow rectangular boxes used in most construction. Since large numbers of electrical boxes necessarily are used in any construction project, even a small additional cost per box frequently results in a prohibitably high expense, so that the mounting aid/box combinations generally are not economically practical.
Other devices have been developed for assisting in the locating and mounting of an electrical outlet box in the space between adjacent wall studs. These are specialty devices and are used only in situations where a precise location of a box, irrespective of the stud location, is required.
A U.S. Patent to Mangin, No. 1,774,934 discloses a device to assist in determining the vertical height of mounting of an electrical box above the floor. The device shown in this patent is a mounting aid attached to the box and which also has a portion mounted on the base plate of the wall. The device, however, of the Mangin Patent is a permanent part of the mounting for the box, and it is left in place once the box is mounted. It is not a separate reusuable tool for locating the box, but necessarily forms an integral part of the box and its mounting. Consequently, a relatively expensive junction box and its associated mounting results. This makes the device of the Mangin Patent impractical for most construction projects.
It is desirable to provide an electrical box locating tool which quickly and accurately facilitates both the vertical location of an electrical box on a stud and the amount by which the box projects from the face of the stud. It is desirable that such a tool is easy to use, relatively inexpensive, and capable of releaseably locating and holding electrical boxes of a standard design in position adjacent a stud for attachment to the stud, whereupon the tool quickly and easily may be removed for subsequent use with additional boxes to be mounted on other studs in the building under construction.